High speed tools material



A. BOERDER.

HIGH SPEED TOOLS MATERIAL.

APPLICATION FILED MAY 15. I918.

1,415,085, Patented May 9, 1922.

' [PR/0R 4/? T/ AvOh-mbmoim/ onirs- STATES PATENT OFFICE.

ANTON BOERDER, OF TOLEDO, OHIO. ASSIGNOR, BY MESNE ASSIGNMENTS, TO U. S HIGH SPEED STEEL & TOOL OORPORATION, OF NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

HIGH SPEED TOOLS MATERIAL Specification of Letters Patent.

Patented May a, 1922.

Application filed May 15, 1918. Serial No. 234,679.

T 0 all whom it may concern:

Be it known that I, ANTON BoERDEn, a citizen of the United States of America, residing at Toledo, Lucas County, Ohio, have invented new and useful High-Speed-Tools Material, of which the following is a specification.

The purpose of this invention is the production of a high speed or other steel tool directly from the molten alloy by casting in the general form in which it is to be used without the preliminary casting in the ingot and the forging to form.

In the manufacture of alloy steel tools, especially high speed tools, as heretofore practiced. it has been necessary to first cast the molten metal compositionas an ingot and then mechanically work the metal to the desired tool form. The metal has not been cast directly in the form in which it is to be used. as when first cast the metal has been of such an internal structure as to be mechanically defective. This defective structure has been overcome, to a 'certain extent, by the forging or other mechanical treatment and various annealing and heat treatments.

The defective structure of the ingot casting is believed to be due to the presence of various impurities in the melt such as phosphorus and sulphur but even more to gaseous substances, occluded or otherwise associated with the metal.

This invention consists in eliminating the causes which produce the defective structure in the ingot by producing a molten comp0- sition of such purity before casting that the operation may be effected directly in the general form of the tool desired whereby the expensive forging and similar operations may be obviated.

This is effected by selecting constituents of such purity and also so purifying and scavenging the melt prior to casting as to greatly reduce or eliminate these disturbingx influences in the cast material.-

eferring to the drawings:

Fig. 1 is an enlarged cross section of a portion of a high speed alloy steel tool prpiduced in accordance with this invention an Fig. 2 is a similar View of an ordinary high speed alloy steel tool showing its internal distorted condition from forging to eliminate internal defects.

A specific example of a mode of practicing the invention will now be given. A graphite crucible is charged with twenty parts of iron, preferably refined iron. This iron' is in small fragments and to it is added twenty five and three fourths parts of ferrotungsten (80% or eighteen parts being tungsten), seven and'one half parts ferrochromium (60% or four and one-half parts being chromium) and five parts ferro-vanadium (30% or one and one-half parts being vanadium). With a charge to total 100 lbs, 8 oz. of ferro-manganese is now added together with 8 oz. of S A M Lion brand metal. Upon this mass in the crucible is dumped forty parts more of the iron for the charge. The crucible is then intensely heated to bring the contents up to a uniformly thin liquid in consistency. As this liquefying stage is approached, and say some twenty minutes before the mass is thoroughly molten for the pouring, 16 oz. of ferro-titanium is added. This time in terval should be such after the addition of this titanium, that the titanium may have just suflicient time for thoroughly dissolving throughout the. metal. This example is in no wise to be held as limiting the invention. The invention is not limited to any particular composition but has as its essential feature the production of a melt of such a char acter that the material can be directly cast.

Molds, as for instance sand molds, are provided of the contour for the finished product. These molds may be provided with chills, as found desirable, especially for assisting in such uniformity of cooling as may best minimize internal stresses in the casting. The high-speed tool steel melt is poured directly into the molds, and the castings therefrom, on cooling, are at once in the finished form for high-speed tools, even to the cutting edge. The surfacemay .be cleaned by sand blast, and in preparing for final finishing of the cutting edge, polishing or sharpening portions of the tool the casting may be annealed, locally groun or machined, and then finally heat treated.

An enlarged section of a cast tool so produced is shown in Fig. 1, which shows the general uniform homogeneous character of the steel as directly cast. There is no compacting, no elongation deformation markings no Stratification-like lines from hammering, rolling or applied force of forging operation. There is no disturbance of the general uniform groupings of the molecules initially taken when the material solidified from a molten mass. These molecules substantially retain their group association with inherent strength and wearing ualities over forged or worked material.

he product is of uniform texture or internal structure throughout with freedom from injurious blow or gas holesf Thiscast tool is a superior teal.

The various ingredients incorporated with the iron may be considered to have various functions in improving 'the material. In this connection, the alloy substances selected for the particular character of tool may be ure or in some combination as with iron. It is desirable that none of the ingredients have deleterious uantities of substances, as sulphur or phosp orus. The less of these volatile impurities the uicker the purifi'cation takes effect hereun er.

The S A M metal may be considered the regular trade alloy on the market, including iron, manganese, aluminum and silicon. The

use of this scavenging alloy may be described as a de-oxidizer in the melt herein, in which it may be further assisted by the added manganese in the ferro-manganese, while the titanium also has purification func tion in assisting in the production of blow-hole free casts as in the driving off of nitrogen. The purification, therefore, as conducted hereunder, eliminates gas from the melt in the production of the uniform internal structure of the cast herein.

What is claimed and it is desired to secure by Letters Patent is:

1. An alloy high speed steel tool free from internal marks as a solid and of uniform in!- ternal structure.

2. A cast high speed steel tool of substantially uniform internal structure.

3. A high'speed tool steel of uniform internal structure and free from internal indications of mechanical working.

4. In the manufacture of steel tools, the production of a melt of the desired composition, purifying such melt for the elimination of defect producing impurities therefrom, and casting such melt directly to approximate tool form.

5. In the manufacture of tool steel, the production of a melt of the desired composition, purifying such melt for the elimination of gas therefrom, and casting such melt form.

9. In the manufacture of cast alloy-high speed tools, producing a melt, purifying such melt to successively eliminate a ortion of the oxidizing constituents and nltrogen, and castin directly to tool form capable of being finis ed by light grinding.

In witness whereof I afiix my signature.

ANTON BOERDER. 

